row

问题 After watching many threads about getting selected rows numbers, I am really confused. How do you get ROW numbers in QTableView using QStandardItemModel I used below selection model and behavior as setSelectionBehavior(QAbstractItemView::SelectRows); setSelectionMode(QAbstractItemView::SingleSelection); and if you have your own way of selecting can you explain how it works. Thanks for the help! 回答1: The method selectionModel() return a QItemSelectionModel . You can use QItemSelectionModel

问题 Using PHP and MySQL, I want to select only 6 rows from table which has more rows everyday. I try to use the code like: SELECT * FROM table WHERE rand()<=$fragment LIMIT 6 where fragment is 6 divided by number of total rows. The number of rows in result mostly be 6, but sometime less than 6. How to get the result that have exactly six rows? 回答1: SELECT * FROM table WHERE some condition ORDER BY RAND() LIMIT 6 回答2: SELECT * FROM table order by rand() limit 6; That will always give you exactly 6

问题 I have 2 dataframes df1 and df2 of different size. df1 = pd.DataFrame({'A':[np.nan, np.nan, np.nan, 'AAA','SSS','DDD'], 'B':[np.nan,np.nan,'ciao',np.nan,np.nan,np.nan]}) df2 = pd.DataFrame({'C':[np.nan, np.nan, np.nan, 'SSS','FFF','KKK','AAA'], 'D':[np.nan,np.nan,np.nan,1,np.nan,np.nan,np.nan]}) My goal is to identify the elements of df1 which do not appear in df2. I was able to achieve my goal using the following lines of code. df = pd.DataFrame({}) for i, row1 in df1.iterrows(): found =

问题 Thanks to Oleg, my jqGrid now looks like this, and works fine. (my problem after the code) var columnModel = [{ name: 'ID', index: 'ID', sortable: true, summaryType:'count', summaryTpl:'<b>{0} Item(s)</b>' }, { name: 'FirstName', index: 'FirstName', sortable: true}, { name: 'LastName', index: 'LastName', sortable: true } ]; var columnNames = ['Id', 'First Name', 'Last Name']; myGrid.jqGrid({ url: './WebService.asmx/ViewNQueryData', datatype: 'json', mtype: 'POST', ajaxGridOptions: {

问题 I am attempting to row bind many data frames together into a single massive data frame. The data frames are named sequentially with the first named df1 , the second named df2 , the third named df3 , etc. Currently, I have bound these data frames together by explicitly typing the names of the data frames; however, for a very large number of data frames (roughly 10,000 total data frames are expected) this is suboptimal. Here is a working example: # Load required packages library(plyr) #

问题 I am attempting to row bind many data frames together into a single massive data frame. The data frames are named sequentially with the first named df1 , the second named df2 , the third named df3 , etc. Currently, I have bound these data frames together by explicitly typing the names of the data frames; however, for a very large number of data frames (roughly 10,000 total data frames are expected) this is suboptimal. Here is a working example: # Load required packages library(plyr) #

问题 I want to get the number of rows from the database, but when I try to do this the $g_check variable will be equal to 0 and my code will echo the $sugg_title message which is in the else statement. But in the database there are 4 inserted groups so the num_rows property should return 4. $sql = "SELECT DISTINCT gp.logo, gp.name FROM gmembers AS gm LEFT JOIN groups AS gp ON gp.name = gm.gname WHERE gp.creator != ? AND gm.mname != ? LIMIT 10"; $stmt = $conn->prepare($sql); $stmt->bind_param('ss',

问题 I am trying to use pipe mutate statement using a custom function. I looked a this somewhat similar SO post but in vain. Say I have a data frame like this (where blob is some variable not related to the specific task but is part of the entire data) : df <- data.frame(exclude=c('B','B','D'), B=c(1,0,0), C=c(3,4,9), D=c(1,1,0), blob=c('fd', 'fs', 'sa'), stringsAsFactors = F) I have a function that uses the variable names so select some based on the value in the exclude column and e.g. calculates

问题 I am trying to use pipe mutate statement using a custom function. I looked a this somewhat similar SO post but in vain. Say I have a data frame like this (where blob is some variable not related to the specific task but is part of the entire data) : df <- data.frame(exclude=c('B','B','D'), B=c(1,0,0), C=c(3,4,9), D=c(1,1,0), blob=c('fd', 'fs', 'sa'), stringsAsFactors = F) I have a function that uses the variable names so select some based on the value in the exclude column and e.g. calculates

问题 I've searched in google there's an easy way to delete a record with confirmation using this code: <asp:templatefield HeaderText="Delete"> <ItemTemplate> <asp:Button ID="deleteButton" runat="server" CommandName="Delete" Text="Delete" OnClientClick="return confirm('Are you sure you want to delete this user?');" /> </ItemTemplate> </asp:templatefield> But when i run it and click delete and clicking "yes" to confirm. this error appears: The GridView 'PendingRecordsGridview' fired event